diff --git a/ts/components/CompositionInput.tsx b/ts/components/CompositionInput.tsx
index ae0a7a5a5f..0e5849d00c 100644
--- a/ts/components/CompositionInput.tsx
+++ b/ts/components/CompositionInput.tsx
@@ -81,6 +81,7 @@ import { FUN_STATIC_EMOJI_CLASS } from './fun/FunEmoji';
 import { useFunEmojiSearch } from './fun/useFunEmojiSearch';
 import type { EmojiCompletionOptions } from '../quill/emoji/completion';
 import { useFunEmojiLocalizer } from './fun/useFunEmojiLocalizer';
+import { MAX_BODY_ATTACHMENT_BYTE_LENGTH } from '../util/longAttachment';
 
 const log = createLogger('CompositionInput');
 
@@ -158,7 +159,6 @@ export type Props = Readonly<{
   onCloseLinkPreview?(conversationId: string): unknown;
 }>;
 
-const MAX_LENGTH = 64 * 1024;
 const BASE_CLASS_NAME = 'module-composition-input';
 
 export function CompositionInput(props: Props): React.ReactElement {
@@ -612,7 +612,7 @@ export function CompositionInput(props: Props): React.ReactElement {
         node.attributes.removeNamedItem('style');
       }
 
-      if (text.length > MAX_LENGTH) {
+      if (Buffer.byteLength(text) > MAX_BODY_ATTACHMENT_BYTE_LENGTH) {
         quill.history.undo();
         propsRef.current.onTextTooLong();
         return;
diff --git a/ts/jobs/helpers/sendNormalMessage.ts b/ts/jobs/helpers/sendNormalMessage.ts
index 574980a4fa..ae5f5008e0 100644
--- a/ts/jobs/helpers/sendNormalMessage.ts
+++ b/ts/jobs/helpers/sendNormalMessage.ts
@@ -55,7 +55,11 @@ import {
 } from '../../util/editHelpers';
 import { getMessageSentTimestamp } from '../../util/getMessageSentTimestamp';
 import { isSignalConversation } from '../../util/isSignalConversation';
-import { isBodyTooLong, trimBody } from '../../util/longAttachment';
+import {
+  isBodyTooLong,
+  MAX_BODY_ATTACHMENT_BYTE_LENGTH,
+  trimBody,
+} from '../../util/longAttachment';
 import {
   markFailed,
   saveErrorsOnMessage,
@@ -607,6 +611,15 @@ async function getMessageSendData({
     targetTimestamp,
   });
 
+  if (
+    maybeLongAttachment &&
+    maybeLongAttachment.size > MAX_BODY_ATTACHMENT_BYTE_LENGTH
+  ) {
+    throw new Error(
+      `Body attachment too long for send: ${maybeLongAttachment.size}`
+    );
+  }
+
   if (body && isBodyTooLong(body)) {
     body = trimBody(body);
   }
diff --git a/ts/util/longAttachment.ts b/ts/util/longAttachment.ts
index 993faef21c..6ecccd60d0 100644
--- a/ts/util/longAttachment.ts
+++ b/ts/util/longAttachment.ts
@@ -3,16 +3,22 @@
 
 import { unicodeSlice } from './unicodeSlice';
 
-const LONG_ATTACHMENT_LIMIT = 2048;
+const KIBIBYTE = 1024;
+const MAX_MESSAGE_BODY_BYTE_LENGTH = 2 * KIBIBYTE;
+
+export const MAX_BODY_ATTACHMENT_BYTE_LENGTH = 64 * KIBIBYTE;
 
 export function isBodyTooLong(
   body: string,
-  length = LONG_ATTACHMENT_LIMIT
+  length = MAX_MESSAGE_BODY_BYTE_LENGTH
 ): boolean {
   return Buffer.byteLength(body) > length;
 }
 
-export function trimBody(body: string, length = LONG_ATTACHMENT_LIMIT): string {
+export function trimBody(
+  body: string,
+  length = MAX_MESSAGE_BODY_BYTE_LENGTH
+): string {
   const sliced = unicodeSlice(body, 0, length);
 
   if (sliced.length > 0) {